oc cluster up won't start after adding the check for port 53 availability

[tnozicka]

oc cluster up won't start because the new check which is wrong!

The check for 53 is wrong because it does not consider ports that are bound to specific IP and fails. Also there should always be an option to disable such check but I can't find one!?

Typically port 53 is widely used by libvirt (dnsmasq), but is bind to specific IP so this should not be an issue.

It worked before...

@csrwng ?

Version

$ oc version
oc v1.5.0-alpha.2+c5868ac-143-dirty
kubernetes v1.5.2+43a9be4
features: Basic-Auth

Steps To Reproduce

1. oc cluster up --version latest --public-hostname 10.34.129.181

Current Result

-- Checking Docker client ... OK
-- Checking Docker version ... OK
-- Checking for existing OpenShift container ... OK
-- Checking for openshift/origin:latest image ... OK
-- Checking Docker daemon configuration ... OK
-- Checking for available ports ... FAIL
   Error: a port needed by OpenShift is not available
   Caused By:
     Error: ports in use: [53]

Expected Result

Work (as it did before)

Additional Information

$ sudo netstat -tulpn | grep ':53 '
tcp        0      0 192.168.122.1:53        0.0.0.0:*               LISTEN      1797/dnsmasq        
udp        0      0 192.168.122.1:53        0.0.0.0:*                           1797/dnsmasq        

$ ip a
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 50:7b:9d:ab:1f:38 brd ff:ff:ff:ff:ff:ff
    inet 10.34.129.181/23 brd 10.34.129.255 scope global dynamic enp0s25
       valid_lft 82335sec preferred_lft 82335sec
    inet6 2620:52:0:2280:527b:9dff:feab:1f38/64 scope global mngtmpaddr dynamic 
       valid_lft 2591973sec preferred_lft 604773sec
    inet6 fe80::527b:9dff:feab:1f38/64 scope link 
       valid_lft forever preferred_lft forever
5: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:2e:ea:b3 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever

[csrwng]

@tnozicka yes that seems wrong. It should not fail because 53 is in use. Taking a look

[tnozicka]

@csrwng thanks
btw. works with

$ oc v1.5.0-alpha.2+e4b43ee-dirty
kubernetes v1.5.2+43a9be4
features: Basic-Auth

[coreydaley]

@csrwng Looks like @smarterclayton broke it with this pull request: #9547

This code: https://github.com/openshift/origin/blob/master/pkg/bootstrap/docker/up.go#L316

Is now calling this function: https://github.com/openshift/origin/blob/master/pkg/bootstrap/docker/up.go#L664 which returns an error that causes an exit, instead of calling this function: https://github.com/openshift/origin/blob/master/pkg/bootstrap/docker/up.go#L673 which would use the alternate dns port instead of just failing and exiting. @smarterclayton might have a better idea of how to fix it as his pull request did quite a bit of refactoring.

[mfojtik]

@jhadvig you was asking me today about this :-)

[csrwng]

I'm working on a fix ... and hopefully extended tests that will help us figure out when we break it in the future.

[csrwng]

Fixed in #12745 (comment)